1. Field
This document relates to searching for points of interest along a driving route.
2. Background of the Related Art
A navigation apparatus typically performs the following functions: (1) determines an optimal driving route from a start point to a destination point based on a map database; (2) detects a current position of a moving object using a Global Positioning System (GPS) signal received from a GPS system and a moving object detection signal generated by a sensor on the moving object (e.g., a gyro sensor and a velocity sensor); (3) maps the detected current position of the moving object to a route point extracted from the map database; and (4) displays the mapped result. The navigation apparatus also typically provides driving guidance information to a driver by displaying and/or speaking the information to the driver that enables the driver to follow the optimal driving route. The navigation apparatus may be mounted on various moving objects, including ships, aircrafts, and the like.
The navigation apparatus also may be programmed to search for Points Of Interest (POIs) around the current position of the moving object. That is, when a user initiates a POI search by providing the navigation apparatus with a search term, the navigation apparatus may provide a preset number of search results corresponding to POIs within a preset distance from the current position of the moving object.
FIG. 1 illustrates a method for searching for POIs using a conventional navigation apparatus.
As illustrated in FIG. 1, a straight line 100 denotes a road over which the moving object travels. A point P denotes a current position of the moving object, and points (a, b, c, d and e) denote POIs within a preset distance from the point P. The POIs were identified by the conventional navigation apparatus in response to a search request submitted by a user. The search request typically includes one or more search terms inputted by the user.
The method used by the conventional navigation apparatus for searching for the POIs is relatively inflexible. For example, if the current position of the moving object is changed from the point P to another point (not shown), the previously-detected points (a, b, c, d and e) may no longer be relevant to the user, as they may have moved so far away from the moving object that they are no longer of interest to the user. Yet, to obtain POIs close enough to the moving object to be of interest, the user must re-input the one or more search terms and the navigation apparatus must re-perform the POI search.
In particular, when the user wishes to go to the nearest POI to his current position, the conventional navigation apparatus may identify point (a) as the nearest POI based on the point P, the current position of the moving object when the user requested the POI search. However, as the moving object moves away from point P, point (a) may no longer be the nearest POI to the moving object. Rather, point (e) or point (b) may become the nearest POI. Moreover, if the moving object moves even farther away from point P, none of the identified points (a)-(d) may be the nearest POI to the moving object. Rather, another as yet unidentified POI may become the nearest POI to the moving object.
In sum, when searching for POIs using a conventional navigation apparatus, the results of the POI search depend on the current position of the moving object, and accordingly, the POI search is repeated whenever the moving object changes its current position.